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Geographic Information Systems

GIS

Geographic Information Systems (GIS) are an
area of IT application with a significantly different history
from forms of information system GIS deals with the storage, representation and
processing of spatial data. Many forms of decision making are spatial in nature
and disciplines such as cartography have sought to represent spatial
relationships. In 1854 John Snow, an English doctor, attempted to get a better
understanding of the problem. He used a map of London to plot the locations of
the homes of Cholera fatalities. He also marked the location of water pumps on
the map. Using this representation it became clear that those with cholera were
clustered around a particular pump. This supported the belief that the disease
was spread by contaminated water. Dr Snow asked for that pump to be closed and
the epidemic subsided. This example indicates how locations plotted on a map
could provide information that wasn't obvious from an analysis of the
non-spatial characteristics of the patients, e.g., their ages, their diet, etc.

Map of cholera patients produced by John
Snow 1854

Spatial applications involve much larger
datasets and more complex processing than traditional business data-processing.
Consequently, the development of sophisticated GIS applications required
the introduction of computer systems that had the necessary speed and storage
capacity to process queries on the larger quantities of data involved. In the
early years of GIS application, the power required could only be provided by
expensive mainframe computers, which could not be easily used in a flexible way
by end users. While personal computers became useful for many applications in
the 1980s, GIS only became feasible on this platform a decade later. So the
development of GIS from data-processing to decision support has lagged
developments in other areas of IS. GIS applications are also characterised by
the need for large amounts of generic data about the geography of the region.

Currently GIS is becoming increasingly integrated with other
forms of IS. Many areas of application of GIS, such as transport and location
planning, have long been of interest to researchers in OR/MS. Other areas of
interest to CMSS members, such as MCDM are now of increasing importance to GIS
researchers.